Concussions: Study says small hits are just as traumatic - Sports Illustrated Vault
Will a helmet be able to spot concussions in real time?
Anti-Concussion Football Helmets Not Fully Enforced By NFL, NCAA, or U.S. High Schools
Helmet evolution to reduce concussions visits SEC
This Helmet Will Save Football. Actually, Probably Not. - The New York Times
2010 Army Football Guide by Army West Point Athletics - Issuu
Football helmets have improved but are far from 'concussion proof' – San Bernardino Sun
Anti-Concussion Football Helmets Not Fully Enforced By NFL, NCAA, or U.S. High Schools
This Flexible Football Helmet Absorbs Hits Like a Car Bumper
NFL hopes to reduce head injuries with helmet experiment
Modern Football Helmets Don't Do Very Much to Reduce Brain Injuries - The Atlantic